基于遗传算法的Ad-hoc网络安全多目标优化认证机制研究

节点的安全性是Ad-hoc网络面临的重要问题,因为通过非安全节点可以窃取、篡改网络中的数据包,甚至对网络造成致命性的破坏。通常情况下,Ad-hoc网络是借助于基于密钥的认证算法来实现节点的安全性保障的,但是这些认证算法并不适用于Ad-hoc的特殊网络环境。将遗传算法应用于节点安全性认证领域,通过基于多目标优化的认证机制,取代了密钥认证机制。通过模拟实验表明,基于多目标优化的认证机制,在Ad-hoc网络环境中,性能较为优越。     

纤维素酶研究进展

对纤维素利用中的核心热点问题——纤维素酶的生态分布、酶的组成、纤维素酶活性功能区、纤维素酶的作用机理、纤维素酶的表达调控的基础研究和纤维素酶的实际应用研究的进展作了综合评述.     

Estimation of Shallow S-Wave Velocity Structure of Two Practical Sites from Microtremors Array Observation in Tangshan Area

Microtremors array observation for estimating S-wave velocity structure from phase velocities of Rayleigh and Love wave on two practical sites in Tangshan area by a China-US joint group are researched.The phase velocities of Rayleigh wave are estimated from vertical component records and those of Love wave are estimated from three-component records of microtremors array using modified spatial auto-correlation method.Haskell matrix method is used in calculating Rayleigh and Love wave phase velocities,and the shallow S-wave velocity structure of two practical sites are estimated by means of a hybrid approach of Genetic Algorithm and Simplex.The results are compared with the PS logging data of the two sites,showing it is feasible to estimate the shallow S-wave velocity structure of practical site from the observation of microtremor array.     

Genetic polymorphism analyses of a novel panel of 19 X-STR loci in the Chinese Uygur ethnic minority

The population genetic data and forensic parameters of 19 X-chromosome short tandem repeat (X-STR) loci in Chinese Uygur ethnic minority are presented. These loci were detected in a sample of 233 (94 males and 139 females) unrelated healthy individuals. We observed 238 alleles at the 19 X-STR loci, with the corresponding gene frequencies spanning the range from 0.0021 to 0.5644. After Bonferroni correction (P>0.0026), there were no significant deviations from Hardy-Weinberg equilibrium. The cumulative power of discrimination in females and males, and the probability of exclusion of the 19 X-STR loci were 0.999 999 999 999 999 999 998 091, 0.999 999 999 999 966, and 0.999 999 986 35, respectively. The cumulative mean exclusion chance was 0.999 999 992 849 in deficiency cases, 0.999 999 999 999 628 in normal trios, and 0.999 999 998 722 in duo cases. The high value of the forensic parameters mentioned above revealed that the novel panel of 19 loci had important values for forensic applications in the Uygur group.     

文本文件比较的算法分析和程序实现

对两个文本文件的内容进行异同比较在数量上作出统计，这在文字信息处理方面有广泛的应用。本文对文件比较作了算法分析，并给出了一个实现该算法的用Visual Basic语言编制的主要程序段。     

Multiobjective optimization and multivariable control of the beer fermentation process with the use of evolutionary algorithms

INTRODUCTIONThefermentationprocesshasgreatscientificandpracticalimportance.Forseveralreasons,qua-litycontrol,forexample,itisimportanttoincludeallkindsoftechnologicaladvancesintheindustrialprocesses.Thisisthemainaimofourresearch,whichisverycomplexduetothenon-linearityofthestudiedphenomena.Themathematicalmodelsfoundinliteratureincludeonlylaboratoyconditions.Amathematicalmodelhasbeendevelopedforthebeerfermentationprocessbecauseoftheadvantagesthatitprovides.Itallowssimulatingwhatcanhappenwhe…     

Algorithm for 2D irregular-shaped nesting problem based on the NFP algorithm and lowest-gravity-center princlple

The nesting problem involves arranging pieces on a plate to maximize use of material. A new scheme for 2D irregular-shaped nesting problem is proposed. The new scheme is based on the NFP （No Fit Polygon） algorithm and a new placement principle for pieces. The novel placement principle is to place a piece to the position with lowest gravity center based on NFP. In addition, genetic algorithm （GA） is adopted to find an efficient nesting sequence. The proposed scheme can deal with pieces with arbitrary rotation and containing region with holes, and achieves competitive results in experiment on benchmark datasets.     

Application of stochastic method to optimum design of energy-efficient induction motors with a target of LCC

INTRODUCTIONMostcountrieshaveimplementednewpoli ciesontheenergysavingandenvironmentpro tection.AmericanPresidentBushsigned“TheComprehensiveNationalEnergyPolicyAct”in1992statingthatnogeneral purpose ,three phaseinductionmotorswillbeallowedintoUnit edStat…     

A large scale screen for genes (3rd chromosome) related to Wingless signaling pathway

INTRODUCTION The Wingless (Wg) signal transduction path-way is an essential pathway in animal development (Wodarz and Nusse, 1998; Siegfried and Perrimon, 1994). The Wg signaling pathway is evolutionarily conserved and involved in numerous developmental processes in both Drosophila and vertebrates. Ho-mologs of both Wg and their signaling components have been identified in vertebrates. The powerful genetics of Drosophila melanogaster provides great opportunity for dissecting the comp…     

一个遗传神经网络预测模型

BP算法是人工神经网络研究的一个常用方法，但从本质上说是属于局部寻优法，容易陷入局部极小点，且存在着学习速度与精度之间的矛盾；遗传算法是一种全局优化算法，具有并行计算能力．本文采用遗传算法来训练前向神经网络，建立一个基于遗传算法和BP算法的神经网络预测模型．试验结果表明它是一个成功较高的预测模型．